48 BULLETIN 120, UNITED STATES NATIONAL MUSEUM. 



The histological condition of the nuclei suggests that these large 

 individuals are not normal. One was found with three medium-sized 

 nuclei, one of which had extruded two chromatin masses into the 

 perinuclear vacuole. Several others were found with but a single 

 nucleus. In all the large individuals the massive chromatin of the 

 nuclei was aggregated into apparently abnormally large clumps and 

 the whole appearance of the nucleus was abnormal. The individual 

 with three nuclei was a bit more slender than is usual for these 

 swollen individuals. Its nuclei, too, were intermediate in size and 

 condition between the nuclei of the slender individuals and those of 

 the large individuals. 



M easurennents of an ordinary hinucleated individual of the larger 

 sort. — Length of body 0.174 mm. ; width of body 0.076 mm. ; length of 

 nucleus 0.03 mm. ; width of nucleus 0.0174 mm. 



PROTOOPALINA ORIENTALIS, new species (fig. 24, p. 49). 



Type. — United States National Museum Cat. No. 16460. 



Host. — Bonibina [Bo7?ihinator'] orientalis (Boulenger), 10 infec- 

 tions. The type infection is from United States National Museum 

 specimen No. 17527, 42 mm. long, from Fusan, Korea, 1885, P. L. 

 Jouy, collector. There are two other infections from the same set of 

 specimens, and there are seven infections from the Yulu River, 

 Southern Manchuria, China, A. de C. Sowerby, collector. 



Measurements of a large individual. — Length of body 0.288 mm. ; 

 width of body 0.063 mm.; length of nucleus 0.0236 mm.; width of 

 nucleus 0.0133 mm. ; diameters of endospherules, respectively, 0.0016 

 mm., 0.0022 mm., 0.0025 mm. ; cilia line interval, anterior 0.0019 mm., 

 posterior 0.004 mm. 



Measurements of a small individual. — Length of body 0.187 mm. ; 

 width of body 0.043 mm. ; length of nucleus 0.02 mm. ; width of 

 nucleus 0.01 mm. 



As in Protoopalina caudata^ so also in P. orientalis we find stocky 

 (fig. 24, (?), and more slender (fig. 24, h) forms and intergracles be- 

 tween the two, though the extremes in either direction are not so 

 much emphasized as they are in P. caudata. In most individuals the 

 body is sharply pointed posteriorly. In some cases the point is not 

 seen, the posterior end being rounded (fig. 24, k and Z), as it is some- 

 times in P. caudata. I'he two nuclei are connected by a thread, as 

 shown in the figures, except in individuals ready for fission, and ex- 

 cept in daughter cells recently come from fission, in which we see a 

 dumb-bell-shaped nucleus (fig. 24, c). The cytological condition of 

 the nucleus has not been studied. 



